Astronaut Luca Parmitano nearly drowned during his spacewalk this morning, NASA officials said during a press conference this afternoon.

During his second walk in two weeks to perform routine maintenance on the International Space Station, the Italian astronaut had one to five liters of water seep into his helmet, impairing his ability to see or hear, NASA officials said.

The unexpected problem forced Mission Control to abort the spacewalk and send Parmitano and his American colleague Chris Cassidy back into the airlock of the International Space Station.

NASA is conducting intensive forensic work to figure out the cause of the leak. The drink bag attached to the suit holds 32 ounces of water and the cooling system holds a gallon.

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Water accumulated inside astronaut Luca Parmitano’s helmet this morning during a spacewalk at the International Space Station, causing Mission Control to abort the walk.

It took 24 minutes to get Parmitano back into airlock and another 11 minutes to get him out of the suit, NASA officials said. The crew inside the space station raced to help him get out of his spacesuit because he was having trouble seeing and hearing at that point.

Cassidy told Mission Control "the water tastes funny, not like our water from the portable water dispenser" after the two were out of their spacesuits, NASA said.

The spacewalk was supposed to last about six and a half hours, but the water problem shortened it to an hour and 32 minutes.

This was the second spacewalk for the two in a week -­ Cassidy was on his sixth spacewalk, and Parmitano was on his second. He was the first Italian astronaut to walk in space when he headed out.

None of the items on the spacewalk to-do list today are critical, but they are important for space station maintenance and to prep the station for a new Russian module that will be coming up to the space station, NASA said.